Simulating the transport of relativistic electrons and magnetic fields injected by radio galaxies in the intracluster medium

Radio galaxies play an important role in the seeding of cosmic rays and magnetic fields in galaxy clusters. Here, we simulate the evolution of relativistic electrons injected into the intracluster medium by radio galaxies. Using passive tracer particles added to magnetohydrodynamical adaptive-mesh s...

Full description

Saved in:
Bibliographic Details
Published in:Astronomy and astrophysics (Berlin) 2021-09, Vol.653, p.A23
Main Authors: Vazza, F., Wittor, D., Brunetti, G., Brüggen, M.
Format: Article
Language:English
Subjects:
Cosmic rays
Electrons
Finite element method
Galactic clusters
Galactic evolution
Magnetic fields
Perturbation
Radio astronomy
Radio galaxies
Radio observation
Relativistic effects
Relativistic particles
Shock waves
Simulation
Stars & galaxies
Tracer particles
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Radio galaxies play an important role in the seeding of cosmic rays and magnetic fields in galaxy clusters. Here, we simulate the evolution of relativistic electrons injected into the intracluster medium by radio galaxies. Using passive tracer particles added to magnetohydrodynamical adaptive-mesh simulations, we calculated the evolution of the spectrum of relativistic electrons, taking into account energy losses and re-acceleration mechanisms associated with the dynamics of the intracluster medium. Re-acceleration can occur at shocks via diffusive shock acceleration, and in turbulent flows via second-order Fermi re-acceleration. This study confirms that relativistic electrons from radio galaxies can efficiently fill the intracluster medium over scales of several hundreds of Myr and that they create a stable reservoir of fossil electrons that remains available for further re-acceleration by shock waves and turbulent gas motions. Our results also show that late evolution of radio lobes and remnant radio galaxies is significantly affected by the dynamics of the surrounding intracluster medium. Here, the diffusive re-acceleration couples the evolution of relativistic particles to the gas perturbations. In the near future, deep radio observations, especially at low frequencies, will be able to probe such mechanisms in galaxy clusters.
ISSN:0004-6361
1432-0746
DOI:10.1051/0004-6361/202140513